The transmitting models of ultrasonic vibration in ultrasonic transducer and capillary were presented according to the propagating mechanism of ultrasonic wave in elastic body. The coupling characteristics of ultrason...The transmitting models of ultrasonic vibration in ultrasonic transducer and capillary were presented according to the propagating mechanism of ultrasonic wave in elastic body. The coupling characteristics of ultrasonic longitudinal-complex transverse vibration system were simulated by Matlab software. The ultrasonic vibration displacement and the velocity of high frequency were measured by using the PSV-400-M2(1.5MHz) laser Doppler vibrometer. The vibration locus shapes driven by the same frequency and different frequencies were tested by using GDS-820S dual channel digital oscilloscope. The microstructures at bonding interface were observed by means of KYKY2800 scanning electron microscope. The results show that ultrasonic vibration displacement or velocity and energy density increase with the decrease of section area in the transmitting process. The vibration locus shapes driven simultaneously by the same frequency and different frequencies are elliptical (or circular) loci and rectangular (or square) loci, respectively. And the characteristics at bonding interface are improved by coupling loci.展开更多
This work presents a short review of the current research on the acousto-optic mechanism applied to optical fibers. The role of the piezoelectric element and the acousto-optic modulator in the excitation of flexural a...This work presents a short review of the current research on the acousto-optic mechanism applied to optical fibers. The role of the piezoelectric element and the acousto-optic modulator in the excitation of flexural and longitudinal acoustic modes in the frequency range up to 1.2 MHz is highlighted. A combination of the finite elements and the transfer matrix methods is used to simulate the interaction of the waves with Bragg and long period gratings. Results show a very good agreement with experimental data. Recent applications such as the writing of gratings under the acoustic excitation and a novel viscometer sensor based on the acousto-optic mechanism are discussed.展开更多
We describe a fiber optic hydrophone array system that could be used for underwater acoustic surveillance applications （e.g. military, counter terrorist, and customs authorities in protecting ports and harbors）, off...We describe a fiber optic hydrophone array system that could be used for underwater acoustic surveillance applications （e.g. military, counter terrorist, and customs authorities in protecting ports and harbors）, offshore production facilities or coastal approaches as well as various marine applications. In this paper, we propose a new approach to underwater sonar systems using the voltage-controlled liquid crystals and simple multiplexing method. The proposed method permits measurement of sound under water at multiple points along an optical fiber using the low cost components and standard single mode fiber, without complex interferometric measurement techniques, electronics or demodulation software.展开更多
文摘The transmitting models of ultrasonic vibration in ultrasonic transducer and capillary were presented according to the propagating mechanism of ultrasonic wave in elastic body. The coupling characteristics of ultrasonic longitudinal-complex transverse vibration system were simulated by Matlab software. The ultrasonic vibration displacement and the velocity of high frequency were measured by using the PSV-400-M2(1.5MHz) laser Doppler vibrometer. The vibration locus shapes driven by the same frequency and different frequencies were tested by using GDS-820S dual channel digital oscilloscope. The microstructures at bonding interface were observed by means of KYKY2800 scanning electron microscope. The results show that ultrasonic vibration displacement or velocity and energy density increase with the decrease of section area in the transmitting process. The vibration locus shapes driven simultaneously by the same frequency and different frequencies are elliptical (or circular) loci and rectangular (or square) loci, respectively. And the characteristics at bonding interface are improved by coupling loci.
文摘This work presents a short review of the current research on the acousto-optic mechanism applied to optical fibers. The role of the piezoelectric element and the acousto-optic modulator in the excitation of flexural and longitudinal acoustic modes in the frequency range up to 1.2 MHz is highlighted. A combination of the finite elements and the transfer matrix methods is used to simulate the interaction of the waves with Bragg and long period gratings. Results show a very good agreement with experimental data. Recent applications such as the writing of gratings under the acoustic excitation and a novel viscometer sensor based on the acousto-optic mechanism are discussed.
文摘We describe a fiber optic hydrophone array system that could be used for underwater acoustic surveillance applications （e.g. military, counter terrorist, and customs authorities in protecting ports and harbors）, offshore production facilities or coastal approaches as well as various marine applications. In this paper, we propose a new approach to underwater sonar systems using the voltage-controlled liquid crystals and simple multiplexing method. The proposed method permits measurement of sound under water at multiple points along an optical fiber using the low cost components and standard single mode fiber, without complex interferometric measurement techniques, electronics or demodulation software.
